oganesson

Oganesson

A parser for chemical formula strings.

API

// ES6
import { tokenize, countElements, getMass } from 'oganesson';

tokenize(<formula>)

// ES5
const oganesson = require('oganesson');

oganesson.tokenize(<formula>)

tokenize(formula)

Tokenizes the given formula.

Arguments

• formula (String): The chemical formula to tokenize.

  Note: The formula does not necessarily have to be valid.

Returns

An object with an array of tokens.

Examples

Valid formula

tokenize('Ba(NO3)2');

[
  {
    "type": "element",
    "value": "Ba"
  },
  {
    "type": "parenthesis",
    "value": "open"
  },
  {
    "type": "element",
    "value": "N"
  },
  {
    "type": "element",
    "value": "O"
  },
  {
    "type": "subscript",
    "value": 3
  },
  {
    "type": "parenthesis",
    "value": "close"
  },
  {
    "type": "subscript",
    "value": 2
  }
]

Invalid, but parseable formula

tokenize('B)(')

[
  {
    "type": "element",
    "value": "B"
  },
  {
    "type": "parenthesis",
    "value": "close"
  },
  {
    "type": "parenthesis",
    "value": "open"
  }
]

Unparseable formula

tokenize('aB)(')

// Throws an error

countElements(tokens)

Counts the number of each element in the given tokens.

Arguments

• tokens (Array): An array of tokens

  Note: The tokens should be in the format that tokenize returns.

Returns

An object with each element mapped to the number of instances it occurs in the tokenization.

Examples

countElements(tokenize('Ba(NO3)2');

{
  "Ba": 1,
  "N": 2,
  "O": 6
}

getMass(counts)

Gets the total mass of the given counts.

Arguments

• counts (Object): The counts of each element.

  Note: The counts should be in the format that countElements returns.

Returns

The total mass of the given counts.

Examples

getMass(countElements(tokenize('Ba(NO3)2')));

261.33

Todo

• Throw an error in either tokenize or countElements when the formula is invalid.